Question

The activation energy for the gas phase isomerization of cyclopropane is 272 kJ. (CH2)3CH3CH=CH2 The rate constant at 718 K is 2.30×10-5 /s. The rate constant will be /s at 753 K.

Answer 1

The answer is:

The rate constant K2 = 1.9 x 10^-4 1/s

The explanation:

According to Arrhenius equation:

ln(k₁/k₂) = Ea/R (1/T₂ - 1/T₁)

when K is the rate constant

and Ea is the activation energy

R is the ideal gas constant

T1 & T2 is a temperature at kelvin

when we have:

Ea = 272 KJ = 272000 J

R is the ideal gas constant 8.3145 J/Kmol

K1 = 2.3 x 10^-5 1/s    K2 = ?? that is we need to calculate

T1 = 718 K     T2 =753 K

So by substitution:

ln(k₁/k₂) = Ea/R (1/T₂ - 1/T₁)

㏑(2.3X10^-5/K2) = [272000/8.314](1/753-1/718)

∴ K2 = 1.9 x 10^-4 1/s